The present invention relates to a novel anti-diabetic agent, which is obtained from the plant Humboldtia decurrens. The invention also provides a pharmaceutical formulation comprising an effective amount of the extract obtained from the plant Humboldtia decurrens and useful in the treatment of diabetes. Further, a process for obtaining the extract from the said plant, and method for treatment of diabetes is also provided. The formulation acts as an inhibitory agent and helps in decreasing Blood Sugar Level.
Humboldtia decurrens, (Fam: Leguminosae) is a moderate sized tree occurring in Western Ghats of Travancore. The use of this plant or any of its parts have never been disclosed to possess anti-diabetic properties as evidenced by Chemical Abstract and Patent search in literature on this genus.
The main object of the invention is to provide a novel anti-diabetic agent which is obtained from the plant Humboldtia decurrens. 
Another object is to provide a novel anti-diabetic formulation comprising an extract obtained from the plant Humboldtia decurrens optionally together with pharmaceutically acceptable additives.
Yet another object of the invention is to provide a process for obtaining the extract from Humboldtia decurrens. 
Still another object is to provide a method for treatment of diabetics.
The invention relates to an anti-diabetic agent obtained from the plant Humboldtia decurrens. The invention also provides a novel anti-diabetic formulation comprising an effect amount of the extract obtained from the plant Humboldtia decurrens optionally together with additives.
Further, the invention provides, a process for obtaining the anti-diabetic agent from the plant Humboldtia decurrens, and a method for treatment of diabetes.
Accordingly, the invention provides a novel anti-diabetic agent obtained from the plant Humboldtia decurrens. Further, the invention provides a novel formulation comprising an effective amount of the extract obtained from the plant Humboldtia decurrens, optionally in combination with a pharmaceutically acceptable carriers, additives, diluents or excipients.
In an embodiment the active ingredient of the formulation is an extract obtained from the roots of the plant Humboldtia decurrens. The concentration of the extract in the formulation may be 15 to 25% by wt.
The antidiabetic formulation is devoid of toxic effects (LD50 greater than 10 g/kg oral in rats). The unique advantage of the formulation produced by the present invention is that it provides an antidiabetic preparation from a readily available renewable source and can be used even in the crude form.
The extract which is used in the formulation of the invention is preferably obtained from the root, specifically from the root nodules of the plant Humboldtia decurrens. 
The process for obtaining the anti-diabetic agent comprises the steps of:
(a) grinding the dried root nodules of Humboldtia decurrens, to fine powder,
(b) extracting the said powder with a non-polar organic solvent for a period ranging from 20-24 hrs. at a temperature in the range of 60-80xc2x0 C.,
(c) optionally refluxing with an organic solvent for a period of 15 to 20 hrs., followed by evaporating the solvent to obtain a residue, and
(d) crystallising the said residue using lower aliphatic alcohol to obtain a white powder.
The extraction is effected in a Soxhlet extractor using nonpolar organic solvent such as petroleum ether or n-hexane for a period ranging from 20-24 hrs at a temperature in the range of 60-80xc2x0 C. The extraction may also be effected by refluxing at a temperature of 55-65xc2x0 C. for a period ranging from 15-20 hrs using organic solvents such as dichloromethane or chloroform.
As stated earlier, the extract obtained from the root of the plant Humboldtia decurrens is dried to obtain a find powder. Preferably this powder is used to prepare the anti-diabetic formulation. The formulation may be prepared according to any method known in the art. The formulation may be intended for oral, parenternal or other use. The formulation for oral use may be in the form of granules, particles, powders, tablets, capsules, liquid syrup, etc. In order to prepare such formulation, any pharmaceutically acceptable organic or inorganic, solid or liquid carrier, excipient, diluent may be used. The formulation may also contain sweetening agent, flavoring agent, colouring and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets containing the active ingredients, are prepared using the extract from roots of Humboldtia decurrens in combination with non-toxic pharmaceutically acceptable carriers or additives.
Suitable examples of the carriers are gelatine, vegetable oils and fats, polypropylene glycol, petroleum resin and coconut oil. Other pharmaceutically acceptable additives such as stabilizers, wetting agents, emulsifiers and the like may also be added. Liquid pharmaceutically accepted additives are selected from Tween 80, gum accacia or cottonseed oil.
The excipients used may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate, granulating and disintegrating agents, such as corn, starch, or alginic acid; binding agents, like starch, gelatin or acacia; and lubricating agents, such as magnesium stearate, stearic acid or talc.
The tablets prepared may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monosterate or glyceryl distearate may also be employed.
For preparation of gelatin capsules for oral use, the active ingredient (extract of the plant Humboldtia decurrens) is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or water or an oil medium, like peanut oil, liquid paraffin or olive oil.
Aqueous suspensions contain the active ingredient (extract of Humboldtia decurrens) in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydropropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be naturally-occurring phosphatide, for example, lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example, polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example, ethyl, or n-propyl p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, and one or more sweetening agents, such as sucrose or saccharin. Oily suspensions may be formulated by suspending the active ingredients in a vegetable oil, for example arachbis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, or example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavoring agents may be added to provide palatable oral preparations. These compositions may be preserved by the addition of an anti-oxidant such as ascorbic acid.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients, for example sweetening, flavoring and coloring agents, may also be present.
Pharmaceutical compositions of the invention may also be in the form of a oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oil, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring gums, for example gumacacia or gum tragacanth, naturally-occurring phosphatides, for example soy bean, lecithin, and esters or partial esters derived from fatty acids and hexitol, anhydrides, for example sorbitan monoleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethyle sorbitan monoleate. The emulsions may also contain sweetening and flavoring agents.
Syrups and elixirs may be formulated with sweetening agents, for example, glycerol, propylene glycol, sorbitor or sucrose. Such formulations may also contain a demulcent, a preservative and flavoring and coloring agents.
The said formulation containing extract from the plant Humboldtia decurrens can be administered to a diabetic patient at dosage level in the range of 1 to 10 g/day. For mammals like a normal human adult, the dosage level may be in the range of 5 mg/kg wt. of the body. The specific dosage used depends upon a number of factors including requirement of the patient, severity of the condition being treated and the pharmacological activity of the formulation being used. The determination of optimum dosages for a particular patient is well-known to those skilled in the art.
The process is further illustrated by the following examples. However, these should not limit the scope of the invention.